Electric vehicles explained: BEV, PHEV, HEV

A quick explainer of the different types of electric vehicles and what the acronyms stand for.

[jeffjo]

A better name for a BEV is a Charge Depleting Electric Vehicle. "Electric Vehicle" means that it is propelled by electric motors. "Charge Depleting" means that you "charge" is by storing electricity in a battery, and continuously (more or less) deplete that charge while driving. And its range is how far it drives before depleting it all.

An HEV is a not a Charge Depleting EV. It is a Charge Sustaining Electric Vehicle. You don't charge it, it maintains an average level of charge itself (more in the next paragraph) and uses that charge to make the gas engine more efficient. Since it doesn't deplete the charge, talking about its electric range is pointless.

Most of the charge sent to an HEVs battery comes from the engine driving both the wheels, and a generator, at the same time. Not from regenerative braking. A typical gas engine might be 25% to 30% efficient while generating enough power to maintain a cruising speed, but can be 40% efficient if it generates more than that. Even with losses associated with the chargeing cycle, the 30% to 60% increase in gasoline utilization results in a net savings of gas.